A3 Problem Solving: Telling the Whole Story on One Sheet

Many problem-solving efforts fail before anyone tries a fix. Someone notices a problem, a meeting agrees on a solution within ten minutes, and a month later the problem is back because nobody checked what was actually causing it. The A3 is a lean practice designed to slow that rush down just enough to get the thinking right, and to fit the whole story on one sheet of paper.

The name comes from the paper size. The Lean Enterprise Institute (LEI) notes that A3 is the international term for a sheet 297 by 420 millimeters, and that the closest U.S. size is the 11-by-17-inch tabloid sheet. The constraint is the point: one page forces you to say only what matters.

This guide explains what an A3 is, walks through the sections of a typical problem-solving A3, and covers how to start one and how leaders use it to coach.

What an A3 Is, and Isn't

LEI describes the A3 report as a Toyota-pioneered practice of getting the problem, the analysis, the corrective actions and the action plan onto a single large sheet, often with graphics. At Toyota, it says, A3s became a standard way to summarize problem-solving, status reports and planning.

LEI is careful to say the A3 has several facets. It can be a template, but LEI states plainly that "an 'A3' is not a template." It works as a storyboard while the work is in progress, a report once it's done, a problem-solving method, a management discipline for coaching people, and, at the deepest level, a way of thinking that someone can follow whether or not they ever fill in the paper.

On a typical problem-solving A3, LEI explains, the left side focuses on the problem and current condition, and the right side on the countermeasures considered, tested and chosen.

The Sections of a Problem-Solving A3

LEI publishes a detailed template from Managing to Learn, John Shook's 2008 book on the A3 process. It starts with a title (what change or improvement are you talking about?) plus the owner and date, then poses a series of questions in seven sections, summarized here.

1. Background: what is the issue, why does it matter, and what specific performance measure needs to improve?
2. Current conditions: what is happening now versus what should be happening? The template asks, "Have you been to the gemba?" It also asks for facts and data, shown visually, and whether the problem can be broken into smaller pieces.
3. Goal: what specific improvement is required, how much, by when? The template warns: "Don't state a countermeasure as a goal!"
4. Analysis: why does the problem exist? It advises using the simplest analysis tool that will show cause and effect down to root cause, from the 5 whys to tools such as fishbone diagrams and Pareto charts, and testing the logic by asking "why?" going down and "therefore" going back up.
5. Recommendations: what are the options? The template says to always start with two or three alternatives and compare their effectiveness, feasibility, costs and benefits, then show clearly how the recommended actions address the causes found in the analysis.
6. Plan: who will do what, when, and how will effectiveness be measured?
7. Follow-up: how will you know whether the plan was followed, whether it worked, what unintended effects might appear, and how will learning be shared?

The last section asks how you will ensure ongoing PDCA. That fits how David Verble, writing for LEI, describes the A3: a way to capture and organize your plan-do-check-act problem-solving thinking.

A Short Hypothetical Example

Imagine a small IT support team for a 40-person company, where many tickets are reopened after being marked solved.

• Background: reopened tickets frustrate staff and eat technician time.
• Current conditions: the owner pulls a month of tickets and finds that most reopens involve password and account issues. She sits with a technician for an afternoon and sees that "solved" is often marked before the user has confirmed the fix.
• Goal: cut reopened tickets by half within two months.
• Analysis: asking why repeatedly leads to the finding that the ticket system closes tickets automatically when the technician replies, and users in other offices often can't test the fix until the next day.
• Recommendations: compare three options: change the auto-close setting, add a confirmation step, or schedule a call-back. Choose the confirmation step plus a later auto-close.
• Plan and follow-up: one technician changes the settings this week; the owner reviews reopen counts weekly for eight weeks and shares results at the team meeting.

All of that fits on one page. Notice that the countermeasure came only after the analysis.

How to Start an A3

David Verble, an LEI faculty member described as one of the first Toyota-trained managers to bring A3 thinking to the United States, says that when people ask where to start writing an A3, he tells them, "Don't start with writing." His answer is, "Start with the thinking."

In his LEI article, Verble makes several practical points:

• The written A3 is the result of A3 thinking, not the process itself.
• Treat the blank sheet as a guide, one box at a time, investigating before you record.
• Don't expect to finish in order; you will learn more and need to revise earlier boxes.
• The finished A3 must tell a story convincing to others, backed by facts.

He draws on Daniel Kahneman's distinction between fast and slow thinking, arguing that A3 work requires deliberately slowing down, because our default is to jump to a solution.

The A3 as a Coaching Tool

LEI emphasizes that the A3 is also a management process. A manager challenges a team member to solve a problem, then coaches by asking questions instead of supplying answers, so the responsibility stays with the person doing the work.

LEI also notes that each A3 has a named owner, whose initials appear in the upper right corner. That person may not have authority over everything the proposal touches, but is clearly responsible for building agreement and getting decisions made. LEI describes this as shifting the conversation from a debate about who owns what to a dialogue about what is the right thing to do.

For a small team, that suggests a simple routine: when someone writes an A3, a peer or manager reviews it with them, asks "how do you know?" at each box, and helps them go back to the facts rather than rewriting the conclusion.

Common Mistakes

• Filling in boxes as paperwork after the decision has already been made.
• Writing a goal that is really a solution, such as "install new software."
• Skipping the visit to see the work and relying on assumptions.
• Offering only one option, so there is nothing to compare.
• Cramming in text in tiny fonts; if it doesn't fit, the thinking probably isn't clear yet.

Key takeaways

• An A3 puts a problem, its analysis, countermeasures and plan on one A3 sheet, close to the U.S. 11-by-17-inch tabloid size.
• LEI stresses that an A3 is a way of thinking and a coaching process, not just a template.
• Go and see the current condition, set a goal that isn't a countermeasure, and find causes before choosing fixes.
• Compare two or three options and link the chosen one clearly to the causes.
• Start with the thinking, expect to revise, and use reviews to ask questions rather than give answers.

Sources

• Lean Enterprise Institute, A3 Report (Lean Lexicon)
• Lean Enterprise Institute, Managing to Learn: Detailed A3 Template (2010)
• Lean Enterprise Institute, Managing to Learn by John Shook (book page)
• David Verble, How to Start the A3 Problem-Solving Process (Lean Enterprise Institute, July 19, 2022)
• Lean Enterprise Institute, Plan, Do, Check, Act (PDCA) (Lean Lexicon)